summaryrefslogtreecommitdiff
path: root/fs/f2fs/xattr.c
blob: 0631b383e21f41b70d75c2e9b5a602892cb416d8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
// SPDX-License-Identifier: GPL-2.0
/*
 * fs/f2fs/xattr.c
 *
 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
 *             http://www.samsung.com/
 *
 * Portions of this code from linux/fs/ext2/xattr.c
 *
 * Copyright (C) 2001-2003 Andreas Gruenbacher <agruen@suse.de>
 *
 * Fix by Harrison Xing <harrison@mountainviewdata.com>.
 * Extended attributes for symlinks and special files added per
 *  suggestion of Luka Renko <luka.renko@hermes.si>.
 * xattr consolidation Copyright (c) 2004 James Morris <jmorris@redhat.com>,
 *  Red Hat Inc.
 */
#include <linux/rwsem.h>
#include <linux/f2fs_fs.h>
#include <linux/security.h>
#include <linux/posix_acl_xattr.h>
#include "f2fs.h"
#include "xattr.h"
#include "segment.h"

static void *xattr_alloc(struct f2fs_sb_info *sbi, int size, bool *is_inline)
{
	if (likely(size == sbi->inline_xattr_slab_size)) {
		*is_inline = true;
		return f2fs_kmem_cache_alloc(sbi->inline_xattr_slab,
					GFP_F2FS_ZERO, false, sbi);
	}
	*is_inline = false;
	return f2fs_kzalloc(sbi, size, GFP_NOFS);
}

static void xattr_free(struct f2fs_sb_info *sbi, void *xattr_addr,
							bool is_inline)
{
	if (is_inline)
		kmem_cache_free(sbi->inline_xattr_slab, xattr_addr);
	else
		kfree(xattr_addr);
}

static int f2fs_xattr_generic_get(const struct xattr_handler *handler,
		struct dentry *unused, struct inode *inode,
		const char *name, void *buffer, size_t size)
{
	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);

	switch (handler->flags) {
	case F2FS_XATTR_INDEX_USER:
		if (!test_opt(sbi, XATTR_USER))
			return -EOPNOTSUPP;
		break;
	case F2FS_XATTR_INDEX_TRUSTED:
	case F2FS_XATTR_INDEX_SECURITY:
		break;
	default:
		return -EINVAL;
	}
	return f2fs_getxattr(inode, handler->flags, name,
			     buffer, size, NULL);
}

static int f2fs_xattr_generic_set(const struct xattr_handler *handler,
		struct user_namespace *mnt_userns,
		struct dentry *unused, struct inode *inode,
		const char *name, const void *value,
		size_t size, int flags)
{
	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);

	switch (handler->flags) {
	case F2FS_XATTR_INDEX_USER:
		if (!test_opt(sbi, XATTR_USER))
			return -EOPNOTSUPP;
		break;
	case F2FS_XATTR_INDEX_TRUSTED:
	case F2FS_XATTR_INDEX_SECURITY:
		break;
	default:
		return -EINVAL;
	}
	return f2fs_setxattr(inode, handler->flags, name,
					value, size, NULL, flags);
}

static bool f2fs_xattr_user_list(struct dentry *dentry)
{
	struct f2fs_sb_info *sbi = F2FS_SB(dentry->d_sb);

	return test_opt(sbi, XATTR_USER);
}

static bool f2fs_xattr_trusted_list(struct dentry *dentry)
{
	return capable(CAP_SYS_ADMIN);
}

static int f2fs_xattr_advise_get(const struct xattr_handler *handler,
		struct dentry *unused, struct inode *inode,
		const char *name, void *buffer, size_t size)
{
	if (buffer)
		*((char *)buffer) = F2FS_I(inode)->i_advise;
	return sizeof(char);
}

static int f2fs_xattr_advise_set(const struct xattr_handler *handler,
		struct user_namespace *mnt_userns,
		struct dentry *unused, struct inode *inode,
		const char *name, const void *value,
		size_t size, int flags)
{
	unsigned char old_advise = F2FS_I(inode)->i_advise;
	unsigned char new_advise;

	if (!inode_owner_or_capable(&init_user_ns, inode))
		return -EPERM;
	if (value == NULL)
		return -EINVAL;

	new_advise = *(char *)value;
	if (new_advise & ~FADVISE_MODIFIABLE_BITS)
		return -EINVAL;

	new_advise = new_advise & FADVISE_MODIFIABLE_BITS;
	new_advise |= old_advise & ~FADVISE_MODIFIABLE_BITS;

	F2FS_I(inode)->i_advise = new_advise;
	f2fs_mark_inode_dirty_sync(inode, true);
	return 0;
}

#ifdef CONFIG_F2FS_FS_SECURITY
static int f2fs_initxattrs(struct inode *inode, const struct xattr *xattr_array,
		void *page)
{
	const struct xattr *xattr;
	int err = 0;

	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
		err = f2fs_setxattr(inode, F2FS_XATTR_INDEX_SECURITY,
				xattr->name, xattr->value,
				xattr->value_len, (struct page *)page, 0);
		if (err < 0)
			break;
	}
	return err;
}

int f2fs_init_security(struct inode *inode, struct inode *dir,
				const struct qstr *qstr, struct page *ipage)
{
	return security_inode_init_security(inode, dir, qstr,
				&f2fs_initxattrs, ipage);
}
#endif

const struct xattr_handler f2fs_xattr_user_handler = {
	.prefix	= XATTR_USER_PREFIX,
	.flags	= F2FS_XATTR_INDEX_USER,
	.list	= f2fs_xattr_user_list,
	.get	= f2fs_xattr_generic_get,
	.set	= f2fs_xattr_generic_set,
};

const struct xattr_handler f2fs_xattr_trusted_handler = {
	.prefix	= XATTR_TRUSTED_PREFIX,
	.flags	= F2FS_XATTR_INDEX_TRUSTED,
	.list	= f2fs_xattr_trusted_list,
	.get	= f2fs_xattr_generic_get,
	.set	= f2fs_xattr_generic_set,
};

const struct xattr_handler f2fs_xattr_advise_handler = {
	.name	= F2FS_SYSTEM_ADVISE_NAME,
	.flags	= F2FS_XATTR_INDEX_ADVISE,
	.get	= f2fs_xattr_advise_get,
	.set	= f2fs_xattr_advise_set,
};

const struct xattr_handler f2fs_xattr_security_handler = {
	.prefix	= XATTR_SECURITY_PREFIX,
	.flags	= F2FS_XATTR_INDEX_SECURITY,
	.get	= f2fs_xattr_generic_get,
	.set	= f2fs_xattr_generic_set,
};

static const struct xattr_handler *f2fs_xattr_handler_map[] = {
	[F2FS_XATTR_INDEX_USER] = &f2fs_xattr_user_handler,
#ifdef CONFIG_F2FS_FS_POSIX_ACL
	[F2FS_XATTR_INDEX_POSIX_ACL_ACCESS] = &posix_acl_access_xattr_handler,
	[F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler,
#endif
	[F2FS_XATTR_INDEX_TRUSTED] = &f2fs_xattr_trusted_handler,
#ifdef CONFIG_F2FS_FS_SECURITY
	[F2FS_XATTR_INDEX_SECURITY] = &f2fs_xattr_security_handler,
#endif
	[F2FS_XATTR_INDEX_ADVISE] = &f2fs_xattr_advise_handler,
};

const struct xattr_handler *f2fs_xattr_handlers[] = {
	&f2fs_xattr_user_handler,
#ifdef CONFIG_F2FS_FS_POSIX_ACL
	&posix_acl_access_xattr_handler,
	&posix_acl_default_xattr_handler,
#endif
	&f2fs_xattr_trusted_handler,
#ifdef CONFIG_F2FS_FS_SECURITY
	&f2fs_xattr_security_handler,
#endif
	&f2fs_xattr_advise_handler,
	NULL,
};

static inline const struct xattr_handler *f2fs_xattr_handler(int index)
{
	const struct xattr_handler *handler = NULL;

	if (index > 0 && index < ARRAY_SIZE(f2fs_xattr_handler_map))
		handler = f2fs_xattr_handler_map[index];
	return handler;
}

static struct f2fs_xattr_entry *__find_xattr(void *base_addr,
				void *last_base_addr, void **last_addr,
				int index, size_t len, const char *name)
{
	struct f2fs_xattr_entry *entry;

	list_for_each_xattr(entry, base_addr) {
		if ((void *)(entry) + sizeof(__u32) > last_base_addr ||
			(void *)XATTR_NEXT_ENTRY(entry) > last_base_addr) {
			if (last_addr)
				*last_addr = entry;
			return NULL;
		}

		if (entry->e_name_index != index)
			continue;
		if (entry->e_name_len != len)
			continue;
		if (!memcmp(entry->e_name, name, len))
			break;
	}
	return entry;
}

static struct f2fs_xattr_entry *__find_inline_xattr(struct inode *inode,
				void *base_addr, void **last_addr, int index,
				size_t len, const char *name)
{
	struct f2fs_xattr_entry *entry;
	unsigned int inline_size = inline_xattr_size(inode);
	void *max_addr = base_addr + inline_size;

	entry = __find_xattr(base_addr, max_addr, last_addr, index, len, name);
	if (!entry)
		return NULL;

	/* inline xattr header or entry across max inline xattr size */
	if (IS_XATTR_LAST_ENTRY(entry) &&
		(void *)entry + sizeof(__u32) > max_addr) {
		*last_addr = entry;
		return NULL;
	}
	return entry;
}

static int read_inline_xattr(struct inode *inode, struct page *ipage,
							void *txattr_addr)
{
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
	unsigned int inline_size = inline_xattr_size(inode);
	struct page *page = NULL;
	void *inline_addr;

	if (ipage) {
		inline_addr = inline_xattr_addr(inode, ipage);
	} else {
		page = f2fs_get_node_page(sbi, inode->i_ino);
		if (IS_ERR(page))
			return PTR_ERR(page);

		inline_addr = inline_xattr_addr(inode, page);
	}
	memcpy(txattr_addr, inline_addr, inline_size);
	f2fs_put_page(page, 1);

	return 0;
}

static int read_xattr_block(struct inode *inode, void *txattr_addr)
{
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
	nid_t xnid = F2FS_I(inode)->i_xattr_nid;
	unsigned int inline_size = inline_xattr_size(inode);
	struct page *xpage;
	void *xattr_addr;

	/* The inode already has an extended attribute block. */
	xpage = f2fs_get_node_page(sbi, xnid);
	if (IS_ERR(xpage))
		return PTR_ERR(xpage);

	xattr_addr = page_address(xpage);
	memcpy(txattr_addr + inline_size, xattr_addr, VALID_XATTR_BLOCK_SIZE);
	f2fs_put_page(xpage, 1);

	return 0;
}

static int lookup_all_xattrs(struct inode *inode, struct page *ipage,
				unsigned int index, unsigned int len,
				const char *name, struct f2fs_xattr_entry **xe,
				void **base_addr, int *base_size,
				bool *is_inline)
{
	void *cur_addr, *txattr_addr, *last_txattr_addr;
	void *last_addr = NULL;
	nid_t xnid = F2FS_I(inode)->i_xattr_nid;
	unsigned int inline_size = inline_xattr_size(inode);
	int err;

	if (!xnid && !inline_size)
		return -ENODATA;

	*base_size = XATTR_SIZE(inode) + XATTR_PADDING_SIZE;
	txattr_addr = xattr_alloc(F2FS_I_SB(inode), *base_size, is_inline);
	if (!txattr_addr)
		return -ENOMEM;

	last_txattr_addr = (void *)txattr_addr + XATTR_SIZE(inode);

	/* read from inline xattr */
	if (inline_size) {
		err = read_inline_xattr(inode, ipage, txattr_addr);
		if (err)
			goto out;

		*xe = __find_inline_xattr(inode, txattr_addr, &last_addr,
						index, len, name);
		if (*xe) {
			*base_size = inline_size;
			goto check;
		}
	}

	/* read from xattr node block */
	if (xnid) {
		err = read_xattr_block(inode, txattr_addr);
		if (err)
			goto out;
	}

	if (last_addr)
		cur_addr = XATTR_HDR(last_addr) - 1;
	else
		cur_addr = txattr_addr;

	*xe = __find_xattr(cur_addr, last_txattr_addr, NULL, index, len, name);
	if (!*xe) {
		f2fs_err(F2FS_I_SB(inode), "lookup inode (%lu) has corrupted xattr",
								inode->i_ino);
		set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK);
		err = -ENODATA;
		f2fs_handle_error(F2FS_I_SB(inode),
					ERROR_CORRUPTED_XATTR);
		goto out;
	}
check:
	if (IS_XATTR_LAST_ENTRY(*xe)) {
		err = -ENODATA;
		goto out;
	}

	*base_addr = txattr_addr;
	return 0;
out:
	xattr_free(F2FS_I_SB(inode), txattr_addr, *is_inline);
	return err;
}

static int read_all_xattrs(struct inode *inode, struct page *ipage,
							void **base_addr)
{
	struct f2fs_xattr_header *header;
	nid_t xnid = F2FS_I(inode)->i_xattr_nid;
	unsigned int size = VALID_XATTR_BLOCK_SIZE;
	unsigned int inline_size = inline_xattr_size(inode);
	void *txattr_addr;
	int err;

	txattr_addr = f2fs_kzalloc(F2FS_I_SB(inode),
			inline_size + size + XATTR_PADDING_SIZE, GFP_NOFS);
	if (!txattr_addr)
		return -ENOMEM;

	/* read from inline xattr */
	if (inline_size) {
		err = read_inline_xattr(inode, ipage, txattr_addr);
		if (err)
			goto fail;
	}

	/* read from xattr node block */
	if (xnid) {
		err = read_xattr_block(inode, txattr_addr);
		if (err)
			goto fail;
	}

	header = XATTR_HDR(txattr_addr);

	/* never been allocated xattrs */
	if (le32_to_cpu(header->h_magic) != F2FS_XATTR_MAGIC) {
		header->h_magic = cpu_to_le32(F2FS_XATTR_MAGIC);
		header->h_refcount = cpu_to_le32(1);
	}
	*base_addr = txattr_addr;
	return 0;
fail:
	kfree(txattr_addr);
	return err;
}

static inline int write_all_xattrs(struct inode *inode, __u32 hsize,
				void *txattr_addr, struct page *ipage)
{
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
	size_t inline_size = inline_xattr_size(inode);
	struct page *in_page = NULL;
	void *xattr_addr;
	void *inline_addr = NULL;
	struct page *xpage;
	nid_t new_nid = 0;
	int err = 0;

	if (hsize > inline_size && !F2FS_I(inode)->i_xattr_nid)
		if (!f2fs_alloc_nid(sbi, &new_nid))
			return -ENOSPC;

	/* write to inline xattr */
	if (inline_size) {
		if (ipage) {
			inline_addr = inline_xattr_addr(inode, ipage);
		} else {
			in_page = f2fs_get_node_page(sbi, inode->i_ino);
			if (IS_ERR(in_page)) {
				f2fs_alloc_nid_failed(sbi, new_nid);
				return PTR_ERR(in_page);
			}
			inline_addr = inline_xattr_addr(inode, in_page);
		}

		f2fs_wait_on_page_writeback(ipage ? ipage : in_page,
							NODE, true, true);
		/* no need to use xattr node block */
		if (hsize <= inline_size) {
			err = f2fs_truncate_xattr_node(inode);
			f2fs_alloc_nid_failed(sbi, new_nid);
			if (err) {
				f2fs_put_page(in_page, 1);
				return err;
			}
			memcpy(inline_addr, txattr_addr, inline_size);
			set_page_dirty(ipage ? ipage : in_page);
			goto in_page_out;
		}
	}

	/* write to xattr node block */
	if (F2FS_I(inode)->i_xattr_nid) {
		xpage = f2fs_get_node_page(sbi, F2FS_I(inode)->i_xattr_nid);
		if (IS_ERR(xpage)) {
			err = PTR_ERR(xpage);
			f2fs_alloc_nid_failed(sbi, new_nid);
			goto in_page_out;
		}
		f2fs_bug_on(sbi, new_nid);
		f2fs_wait_on_page_writeback(xpage, NODE, true, true);
	} else {
		struct dnode_of_data dn;

		set_new_dnode(&dn, inode, NULL, NULL, new_nid);
		xpage = f2fs_new_node_page(&dn, XATTR_NODE_OFFSET);
		if (IS_ERR(xpage)) {
			err = PTR_ERR(xpage);
			f2fs_alloc_nid_failed(sbi, new_nid);
			goto in_page_out;
		}
		f2fs_alloc_nid_done(sbi, new_nid);
	}
	xattr_addr = page_address(xpage);

	if (inline_size)
		memcpy(inline_addr, txattr_addr, inline_size);
	memcpy(xattr_addr, txattr_addr + inline_size, VALID_XATTR_BLOCK_SIZE);

	if (inline_size)
		set_page_dirty(ipage ? ipage : in_page);
	set_page_dirty(xpage);

	f2fs_put_page(xpage, 1);
in_page_out:
	f2fs_put_page(in_page, 1);
	return err;
}

int f2fs_getxattr(struct inode *inode, int index, const char *name,
		void *buffer, size_t buffer_size, struct page *ipage)
{
	struct f2fs_xattr_entry *entry = NULL;
	int error;
	unsigned int size, len;
	void *base_addr = NULL;
	int base_size;
	bool is_inline;

	if (name == NULL)
		return -EINVAL;

	len = strlen(name);
	if (len > F2FS_NAME_LEN)
		return -ERANGE;

	if (!ipage)
		f2fs_down_read(&F2FS_I(inode)->i_xattr_sem);
	error = lookup_all_xattrs(inode, ipage, index, len, name,
				&entry, &base_addr, &base_size, &is_inline);
	if (!ipage)
		f2fs_up_read(&F2FS_I(inode)->i_xattr_sem);
	if (error)
		return error;

	size = le16_to_cpu(entry->e_value_size);

	if (buffer && size > buffer_size) {
		error = -ERANGE;
		goto out;
	}

	if (buffer) {
		char *pval = entry->e_name + entry->e_name_len;

		if (base_size - (pval - (char *)base_addr) < size) {
			error = -ERANGE;
			goto out;
		}
		memcpy(buffer, pval, size);
	}
	error = size;
out:
	xattr_free(F2FS_I_SB(inode), base_addr, is_inline);
	return error;
}

ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
{
	struct inode *inode = d_inode(dentry);
	struct f2fs_xattr_entry *entry;
	void *base_addr, *last_base_addr;
	int error;
	size_t rest = buffer_size;

	f2fs_down_read(&F2FS_I(inode)->i_xattr_sem);
	error = read_all_xattrs(inode, NULL, &base_addr);
	f2fs_up_read(&F2FS_I(inode)->i_xattr_sem);
	if (error)
		return error;

	last_base_addr = (void *)base_addr + XATTR_SIZE(inode);

	list_for_each_xattr(entry, base_addr) {
		const struct xattr_handler *handler =
			f2fs_xattr_handler(entry->e_name_index);
		const char *prefix;
		size_t prefix_len;
		size_t size;

		if ((void *)(entry) + sizeof(__u32) > last_base_addr ||
			(void *)XATTR_NEXT_ENTRY(entry) > last_base_addr) {
			f2fs_err(F2FS_I_SB(inode), "list inode (%lu) has corrupted xattr",
						inode->i_ino);
			set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK);
			f2fs_handle_error(F2FS_I_SB(inode),
						ERROR_CORRUPTED_XATTR);
			break;
		}

		if (!handler || (handler->list && !handler->list(dentry)))
			continue;

		prefix = xattr_prefix(handler);
		prefix_len = strlen(prefix);
		size = prefix_len + entry->e_name_len + 1;
		if (buffer) {
			if (size > rest) {
				error = -ERANGE;
				goto cleanup;
			}
			memcpy(buffer, prefix, prefix_len);
			buffer += prefix_len;
			memcpy(buffer, entry->e_name, entry->e_name_len);
			buffer += entry->e_name_len;
			*buffer++ = 0;
		}
		rest -= size;
	}
	error = buffer_size - rest;
cleanup:
	kfree(base_addr);
	return error;
}

static bool f2fs_xattr_value_same(struct f2fs_xattr_entry *entry,
					const void *value, size_t size)
{
	void *pval = entry->e_name + entry->e_name_len;

	return (le16_to_cpu(entry->e_value_size) == size) &&
					!memcmp(pval, value, size);
}

static int __f2fs_setxattr(struct inode *inode, int index,
			const char *name, const void *value, size_t size,
			struct page *ipage, int flags)
{
	struct f2fs_xattr_entry *here, *last;
	void *base_addr, *last_base_addr;
	int found, newsize;
	size_t len;
	__u32 new_hsize;
	int error;

	if (name == NULL)
		return -EINVAL;

	if (value == NULL)
		size = 0;

	len = strlen(name);

	if (len > F2FS_NAME_LEN)
		return -ERANGE;

	if (size > MAX_VALUE_LEN(inode))
		return -E2BIG;
retry:
	error = read_all_xattrs(inode, ipage, &base_addr);
	if (error)
		return error;

	last_base_addr = (void *)base_addr + XATTR_SIZE(inode);

	/* find entry with wanted name. */
	here = __find_xattr(base_addr, last_base_addr, NULL, index, len, name);
	if (!here) {
		if (!F2FS_I(inode)->i_xattr_nid) {
			error = f2fs_recover_xattr_data(inode, NULL);
			f2fs_notice(F2FS_I_SB(inode),
				"recover xattr in inode (%lu), error(%d)",
					inode->i_ino, error);
			if (!error) {
				kfree(base_addr);
				goto retry;
			}
		}
		f2fs_err(F2FS_I_SB(inode), "set inode (%lu) has corrupted xattr",
								inode->i_ino);
		set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK);
		error = -EFSCORRUPTED;
		f2fs_handle_error(F2FS_I_SB(inode),
					ERROR_CORRUPTED_XATTR);
		goto exit;
	}

	found = IS_XATTR_LAST_ENTRY(here) ? 0 : 1;

	if (found) {
		if ((flags & XATTR_CREATE)) {
			error = -EEXIST;
			goto exit;
		}

		if (value && f2fs_xattr_value_same(here, value, size))
			goto same;
	} else if ((flags & XATTR_REPLACE)) {
		error = -ENODATA;
		goto exit;
	}

	last = here;
	while (!IS_XATTR_LAST_ENTRY(last)) {
		if ((void *)(last) + sizeof(__u32) > last_base_addr ||
			(void *)XATTR_NEXT_ENTRY(last) > last_base_addr) {
			f2fs_err(F2FS_I_SB(inode), "inode (%lu) has invalid last xattr entry, entry_size: %zu",
					inode->i_ino, ENTRY_SIZE(last));
			set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK);
			error = -EFSCORRUPTED;
			f2fs_handle_error(F2FS_I_SB(inode),
						ERROR_CORRUPTED_XATTR);
			goto exit;
		}
		last = XATTR_NEXT_ENTRY(last);
	}

	newsize = XATTR_ALIGN(sizeof(struct f2fs_xattr_entry) + len + size);

	/* 1. Check space */
	if (value) {
		int free;
		/*
		 * If value is NULL, it is remove operation.
		 * In case of update operation, we calculate free.
		 */
		free = MIN_OFFSET(inode) - ((char *)last - (char *)base_addr);
		if (found)
			free = free + ENTRY_SIZE(here);

		if (unlikely(free < newsize)) {
			error = -E2BIG;
			goto exit;
		}
	}

	/* 2. Remove old entry */
	if (found) {
		/*
		 * If entry is found, remove old entry.
		 * If not found, remove operation is not needed.
		 */
		struct f2fs_xattr_entry *next = XATTR_NEXT_ENTRY(here);
		int oldsize = ENTRY_SIZE(here);

		memmove(here, next, (char *)last - (char *)next);
		last = (struct f2fs_xattr_entry *)((char *)last - oldsize);
		memset(last, 0, oldsize);
	}

	new_hsize = (char *)last - (char *)base_addr;

	/* 3. Write new entry */
	if (value) {
		char *pval;
		/*
		 * Before we come here, old entry is removed.
		 * We just write new entry.
		 */
		last->e_name_index = index;
		last->e_name_len = len;
		memcpy(last->e_name, name, len);
		pval = last->e_name + len;
		memcpy(pval, value, size);
		last->e_value_size = cpu_to_le16(size);
		new_hsize += newsize;
		/*
		 * Explicitly add the null terminator.  The unused xattr space
		 * is supposed to always be zeroed, which would make this
		 * unnecessary, but don't depend on that.
		 */
		*(u32 *)((u8 *)last + newsize) = 0;
	}

	error = write_all_xattrs(inode, new_hsize, base_addr, ipage);
	if (error)
		goto exit;

	if (index == F2FS_XATTR_INDEX_ENCRYPTION &&
			!strcmp(name, F2FS_XATTR_NAME_ENCRYPTION_CONTEXT))
		f2fs_set_encrypted_inode(inode);
	f2fs_mark_inode_dirty_sync(inode, true);
	if (!error && S_ISDIR(inode->i_mode))
		set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_CP);

same:
	if (is_inode_flag_set(inode, FI_ACL_MODE)) {
		inode->i_mode = F2FS_I(inode)->i_acl_mode;
		inode->i_ctime = current_time(inode);
		clear_inode_flag(inode, FI_ACL_MODE);
	}

exit:
	kfree(base_addr);
	return error;
}

int f2fs_setxattr(struct inode *inode, int index, const char *name,
				const void *value, size_t size,
				struct page *ipage, int flags)
{
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
	int err;

	if (unlikely(f2fs_cp_error(sbi)))
		return -EIO;
	if (!f2fs_is_checkpoint_ready(sbi))
		return -ENOSPC;

	err = f2fs_dquot_initialize(inode);
	if (err)
		return err;

	/* this case is only from f2fs_init_inode_metadata */
	if (ipage)
		return __f2fs_setxattr(inode, index, name, value,
						size, ipage, flags);
	f2fs_balance_fs(sbi, true);

	f2fs_lock_op(sbi);
	f2fs_down_write(&F2FS_I(inode)->i_xattr_sem);
	err = __f2fs_setxattr(inode, index, name, value, size, ipage, flags);
	f2fs_up_write(&F2FS_I(inode)->i_xattr_sem);
	f2fs_unlock_op(sbi);

	f2fs_update_time(sbi, REQ_TIME);
	return err;
}

int f2fs_init_xattr_caches(struct f2fs_sb_info *sbi)
{
	dev_t dev = sbi->sb->s_bdev->bd_dev;
	char slab_name[32];

	sprintf(slab_name, "f2fs_xattr_entry-%u:%u", MAJOR(dev), MINOR(dev));

	sbi->inline_xattr_slab_size = F2FS_OPTION(sbi).inline_xattr_size *
					sizeof(__le32) + XATTR_PADDING_SIZE;

	sbi->inline_xattr_slab = f2fs_kmem_cache_create(slab_name,
					sbi->inline_xattr_slab_size);
	if (!sbi->inline_xattr_slab)
		return -ENOMEM;

	return 0;
}

void f2fs_destroy_xattr_caches(struct f2fs_sb_info *sbi)
{
	kmem_cache_destroy(sbi->inline_xattr_slab);
}